"It's now or never." That was the warning of UN scientists yesterday as they unveiled a new plan to keep global heating down to 1.5C and save the world from the worst ravages of the climate crisis.

The stakes could not be higher. Just last week, the Intergovernmental Panel on Climate ChangeA UN body tasked with researching climate breakdown and coming up with recommendations for states to follow. (IPCC) warned that the impacts of climate breakdown are already worse than expected. Three billion lives are now at risk from the crisis.

Even if global temperature increase is kept to 1.5C, up to 14% of species face a very high risk of extinction. In 2019, Australia recorded the first mammal species to have been wiped out by human-made climate change: the Bramble Cay melomysA rodent that went extinct in 2019. The whole species had been dependent on a single coral cay on the Great Barrier Reef; repeated flooding destroyed its habitat..

Even if all states keep their current promises to reduce emissions, global temperatures will still rise by almost 2.5C. That is why the IPCC has warned that more drastic action is needed.

If the global temperature rise is to be kept down to 1.5C, emissions must peak in 2025 and shrink by 43%. The IPCC's new report lays out five steps for achieving this goal:

Cut coal

Coal is responsible for almost one-third of total global heating to date. Yet recent gas shortages have encouraged some governments to consider reintroducing it to their energy mix. The report is clear: to stay below 1.5C, we must stop burning coal. We also have to switch from all kinds of fossil fuels to renewables - and do it fast. 

New technology

Previously, scientists have often been cool on the idea of using big technological fixes for global heating. Plans to spray particles into the atmosphere or put reflective shields in space have received short shrift. But now the IPCC claims there is no solution to the climate crisis that does not involve removing carbon from the atmosphere directly. And for this, we need new technology.

End subsidies

The IPCC is eager to stress that the green transition is now less expensive than the alternative. A temperature rise of 2C by 2050 would reduce global GDP by as much as 7.5%. So scrapping subsidiesMoney given by the state or another body to help keep prices low.  for fossil fuels would reduce emissions by up to 10% by 2030 and save money twice over.

Change demand

The global economy is currently structured around fossil fuels. That means ordinary patterns of spending reinforce the climate crisis. The report recommends that "choice architectureAn idea taken from behavioural economics. It means nudging consumers to make particular choices, sometimes without them even realising it." can be used to shift consumer demand towards low-carbon options. That alone could result in as much as a 70% reduction in emissions by 2050.

Revolutionise everything

The big takeaway from the report is that everything must change. The climate crisis can only be solved with massive reforms in all sectors of the global economy.

But the report is not without its critics. Some environmentalists think the IPCC has given in to fossil-fuel countries. As a result, they claim, it has put undue focus on untested technologies instead of the necessary shift away from dirty energy.

Yes: It is easy to be fatalistic about the climate crisis, which is already wreaking havoc all around us. The new report shows there is a clear path to a better future, and it will not even cost much.

No: The IPCC can lay out recommendations but it is up to individual states to make the changes, and so far, despite the looming crisis, there has been little appetite for grand reforms.

Or... The new report probably will not be implemented. But it does show that it is now cheaper for states to cut their emissions than to keep polluting. That might be enough to persuade them to make some reforms.